1. Field of the Preferred Embodiment
This invention relates generally to a medical device and more particularly to medical device used to manipulate a radioactive needle in surgical procedures such as brachytherapy.
2. The Prior Art
It is well known in the art to use brachytherapy to treat prostate cancer. Reports date back to the early 1900s of brachytherapy being used in the treatment of prostate cancer. Radium needles were initially used, however this was abandoned over time because of radiation exposure to the hands of the surgeon, as well as the fact that radium is not an ideal isotope for such a procedure. In the 1970s, the use of iodine-125 was performed using a suprapubic open surgical technique. This procedure proved unsuccessful and it was abandoned in the early 1980s. In 1993, after the development of the transrectal ultrasound, brachytherapy once again surfaced in the treatment of prostate cancer.
Using a transperineal approach and the use of a template, needles are inserted into the prostate in an exact fashion. The results of this procedure have proven successful, and prostate brachytherapy is now one of the preferred treatments in the management of early-stage prostate cancer.
In brachytherapy treatment of prostate cancer, transrectal ultrasound is used to visualize the prostate. The patient is then implanted with radioactive seeds using twenty (20) centimeter long, 18-gage needles to deposit radioactive iodine-125 or palladium-103 radioactive seeds. These seeds are distributed through the prostate evenly, resulting in a uniform dose of radiation.
The physical characteristics of iodine-125 and palladium-103 are much superior to radium or other isotopes for the purpose of permanent implantation in the prostate gland. The radiation energy is quite low and has a limited exposure rate to the body structures located around the prostate. However, the needles themselves, when filled with radioactive isotopes, do exhibit significant radiation exposure at the surface of the needle and up to a distance of six (6) centimeters. Therefore, if the surgeon's hands or fingers come within a six (6) centimeter radius of the needle, the surgeon will be exposed to radiation. Such exposure is undesirable.
In the past, surgeons have used a fifteen (15) to twenty (20) centimeter stainless steel ruler to assess the depth of needle insertion into the prostate gland. This is a useful aid in exact implantation of the prostate. To control the direction of insertion of the needle once the needle is inside the patient, surgeons have used their fingers to guide and manipulate the needle. Significant exposure to radiation can result to the fingers and hands of the surgeon while touching the needle that houses the radioactive seeds prior to deposition in the prostate gland.